Belarusians in Ukraine (Belarusian: Беларусы Украіны, romanized: Biełarusy Ukrainy; Ukrainian: Білоруси в Україні, romanized: Bilorusy v Ukraini) are the third biggest minority after Russians. Unlike many other ethnic groups, Belarusians do not have any particular concentration in the country, but spread out relatively evenly across all regions.

During the Russo-Ukrainian War Belarusian volunteers fought alongside Ukraine. The first foreign volunteer group in Ukraine was the Pahonia detachment, founded in 2014 during the war in Donbas.^[3] The following year, the tactical group "Belarus" was formed uniting Belarusian volunteers fighting in different battalions^[4] The Monument to the Belarusians who died for Ukraine in Kyiv is dedicated to the Belarusian volunteers who died during the Russian-Ukrainian War.^[5] On March 9, 2022, the creation of the Kastuś Kalinoŭski Battalion was announced which was later transformed into a regiment.^[6] On March 30, 2022, the beginning of the formation of another Belarusian unit, the Pahonia Regiment was announced which is part of the International Legion of Territorial Defence of Ukraine.^[7]

In June 2023, Valery Sakhashchyk, effective defence minister of the Belarusian United Transitional Cabinet (a government-in-exile opposed to the de facto government of Alexander Lukashenko) informed about the creation of the 1st separate air assault company "Belarus", which is part of the 79th Air Assault Brigade.^[8] The Belarusian assault company is located in the Donetsk direction.^[9]

In Ukraine, the number of Belarusians is estimated at over 275,000 (the 2001 Ukrainian Census).^[10] Most of the Belarusians diaspora in Ukraine appeared as a result of the migration of Belarusians to the Ukrainian SSR during the Soviet Union. Lviv has been an important center of Belarusian social and cultural life during the Russian Empire and interwar Poland. There are now Belarusian organizations in major cities like Lviv, Sevastopol in the Crimea, and others. A notable Ukrainian of Belarusian descent is Viktor Yanukovych, the fourth president of Ukraine.

• Belarus–Ukraine relations
• Belarusian language in Ukraine
• Ukrainians in Belarus